Improvement in



UNITED FFICE.

IMPROVEMENT litiv SAW-NHLLS.

Specification forming part of Letters Patent No. 9&0E3, dated December 2l, 18 9.

To 'whom it may concern:

I, AsnBELL l?. BARLow, of Kalamazoo, in. the county of Kalamazoo, in the State of Michi# lower side of the log or stock, with the lowerteeth of the saw, and so that the saw, in its downward motion, will bring the next succeeding tooth above the rst, in contact with the wood, and so on, advancing each tooth of the saw in succession to the upper one that strikes the wood, by means of two (upper and lower) sets of straight guides, the upper set inclined, the lower perpendicular, which give the direction and relative posit-ion of the saw with the log, in connection with the manner of pivoting or attaching the lower end oi' the saw to the pitman.

In the accompanying drawings, Figure l is a front view of my invention. Fig. 2 is a side elevation. Fig. 3 shows the different positions of the bottom of the saw when the pitman is in different positions on the crank-wheel. Fig. 4 is another view of the saw at the diiierent points of its downward reciprocation. Fig. 5 is a view of one side of the upper muleyhead, and Fig. 6 is a view of one side of the lower muleyhead, showing the grooves in which the guide-pin slides.

In the accompanying drawings, A represents the upright supporting-posts; Af A', the upper and lower cross-girders, and to which are attached the upper and lawerinuley-heads. B B are the two sides of the upper muley-head, to which are attached the adjustable plates a a, having the straight single inclined guides a a', which are adjustable upon the muley-heads by means of set-screws and slots. a" is the crosshead, which is constructed to fit and slide freely upon theinclined guidesa/a'. bis theuppersawbuckle, that connects the saw C with the crosshead a. B B are the two sides of the lower muley-blocks, and have straight perpendicular grooves, b', in their inner surfaces, as seen in Fig. 6. cis the lower saw-buckle, and connects the saw U to the pivot-pin c of the pitrnan. c is the pitman, bifurcated at its top end, and journaled upon the wrist-pin h of the crank-wheelf, and has, at or near to its top end, and upon the outside of each limb of the bii'urcated pitman,fulcru1n or guide pins, (l, which pins d lit and freely slide in the grooves b of the heads B. g is the driving revolving shaft that gives motion to the crank-wheel f, in the usual manner. 'lhc side view, Fig. 2, shows the saw in the position that it has after it has made its downward stroke, and is ready V'to rise, while in Figs. 3 and 4 other positions of the saw are shown. The dotted lines in Fig. 3 show the bottom of the saw advanced, when one-eighth of the revolution of the crankwheel has been made, which gives the saw, at

the commencement ot' its downward stroke, a forward motion by reason of attaching the sawbuckle to the pit-man below the fulcrum or guide pins; and in Fig. et the heavy broken/ lines i show the position of the saw when it is at its extreme upward reciprocation, with its upper end back from the perpendicular of the pivoted point, where it is connected to the pitinan. The light broken linesj show the position ot' the saw when it has made one-haltl of its downward stroke, and the light whole lines k give the position ot' the saw when it has reached its full downward reciprocation.

The straight single inclincs of the guides, as above described, are intended to define a different construction from what is known as double inclines, or where the guides, on their faces, have two different angles of inclina-tion in their length, and each division of the inclination has the face of the guide or straight lines, but only extend half the length of the guide before the inclination is changed to a dii-ferent angle, while in this invention the same angle of inclination extends the whole length of the guides.

B y this arrangement of straight inclined upper guides operating together, with the connecting the saw to the pitman below or above the fulcruln or guide pins, which slide in perpendicularcgrooves, it will be seen that the Ybottom or lower teeth of the saw areirst brought into contact with the timber, and as the saw reciprocates downward the succeeding teeth above come into contact with the 2 JQADRS timber, in succession, until the upper teeth become the last to strike the timber at the top of the log, thus distributing equally, among all the teeth of the saw that are brought into the operation of cutting away the timber, the labor and strain of the act of sawing, instead of having some of the teeth do double the Work of others in cutting the timber, as is generallyr` the oase.

I lay 11o claim to the use of straight inclined guides7 or to the pivoting'the saw to the pitman above or below the fulcrurn or guide pins, as both of these have been used singly.

Having thus described my invention, what I desire to secure by Letters Patent is- The combination of the straight single inelined upper guides a a' and cross-head a with the saw C and pitman e, when the saw is pivote-d to the pitman, either above or below the pitmanfulerun1 or guide-pins d, in the manner and for the purpose substantially as described.

ASHBELL I. BARLOW. Witnesses z" NEWTON CRAWFORD, EDM. F. BROWN. 

